Generator mounting



Feb. 1949. w; K. BODG ER 2,451,195

GENERATOR MOUNTING 7 Filed Jan. 30, 1945 v 3 Sheets-Sheet l INVENTORFeb. 8, .1949. w. K. BODGER GENERATOR MOUNTING 3 Sheets- Sheet 2 FiledJan; 30, 1945 INVENTOR MW Patented Feb. 8, 1949 .Walter Kenneth Bodger,

South Glastonbury,

Conn., assignor to United Aircraft Corporation, East Hartford, Conn., acorporation or Delaware Application January 30, 1945. Serial No. 575,347

Claims. (01. 80-.44)

This invention relates to the assembly of 'a number of gas generatorsaround a central gas collector, particularly for use in aircraft powerplants.

In the copending Kalitinsky application, Serial No. 531,303, now PatentNo. 2,441,196, is shown a power plant installation in which a number offree-piston units, each functioning as a gas generator, are arrangedaround a central gas collector from which the gas discharges through aburner to a turbine. A feature of this invention is an arrangement bywhich the generators may be supported directly by the collector. Anotherfeature is the separate support of groups of generators spacedlengthwise of the collector.

' In the copending Thompson application, Serial No. 575,346, filedJanuary 30, 1945, a power plant of this type is shown in which the gascollector is made rigid enough to act as a cantilever on which thegenerators may be mounted. A feature of this invention is a gascollector which,

except for the bands where the generators are mounted, is relativelythin and is required to carry substantially no otherload than thepressure load resulting from the gas within the collector.

Other objects and advantages will be apparent from the specification andclaims, and from the accompanying drawings which illustrate anembodiment of the invention.

Fig. 1' is a side elevation of the power plant.

Fig. 2 is an end elevation of the generators and burner of Fig. 1.

Fig. 3 is a sectional view through one of the generators and showing itsattachment to the gas collector. I

Each unit 8, as shown in Fig. 3, includes an engine cylinder ilLhavingreciprocating pistons i2 and II to which compressor pistons I6 and i8 incylinders and 22 are integrally connected. Sleeves 24 and 26 attached tothe compressor pistons complete the reciprocating piston assemblies. Thesleeve in combination with stationary pistons 28 and 30 form air springcylinders.

The piston assemblies are moved apart by the burning of fuel injectedinto engine cylinder I'D through one or more nozzles 32. Air compressedin the air spring cylinders on the power stroke returns the pistonassemblies. The assemblies are always maintained at equal distances fromthe center of the engine cylinder by a linkage, not shown.

ters opposite ends of the cylinders. The compressed air leaves thecylinders through discharge valves 48, also at opposite ends of thecompressor cylinders and passes into a central scavenge chamber 48 andend chambers 50 and 52. These chambers may be interconnected by ascavenge manifold, not shown.

Compressed gas from the scavenge chambers enters engine ports 54 and 58which are uncov-' ered by pistons l2 and it at the end of the powerstroke, thereby permitting air to be blown through the engine cylinder.Gas in the engine cylinders is discharged through exhaust ports 58 intoexhaust manifold 80.

Exhaust gas from the generators is discharged into an exhaust collector62 to which the exhaust manifolds 60 are connected. 'In the arrangementshown, the generators are arranged in groups of four, substantiallyuniformly spaced about the collector, the groups being longitudinallyspaced from each other along the collector.

The exhaust collector may have a centrally located combustion chamber 64in the form of a duct connected by a duct 65 to the inlet of a turbine66. If the power plant is used for aircraft the turbine may be connectedthrough gear reduction units 68 and 'Hiand shafts l2 and 74 to a shaft18 on which a propeller system may be mounted.

The exhaust collector is surrounded by a scavenge collector 80 whichreceives the gas from the compressors of the free-piston units anddelivers gas to the scavenge ports in the engine cylinders. The scavengecollector is relatively cool and is Intake manifold 42 which extendsaround the subject primarily to scavenge gas.

For supportingthe generators the scavenge collector has flanges 82 towhich are directly connected the mounting-flanges 84 on the case 88 thatsurrounds the free-piston unit and within which case the severalelements of the freepiston unit are supported. The end scavenge chambers50 and 52 may be connected to mounting flanges 88 and 90 on the scavengecollector, and it will be noted that the flanges 8B and iii arerelatively thin so that they do not carry any appreciable load otherthan the pressure loading from the scavenge gas.

the pressure load of the The scavenge collector is reinforcedcircumferentially at the point where the mounting flanges 82 areprovided by being thicker as indicated at 92 in Fig. 1. This reinforcingmay be integral with the collector or may include heavy circumferentialribbing. v In either event, the reinforcement at this section issumcient to supwin port without distortion the individual generatorswith the entire weight of the generator carried by the reinforcedsection of the burner. The case 86 of the free-piston unit forms theloadcarrying member and since it is directly connected to the flanges 82each generator may be cantilevered to the reinforced section of the'burner without additional external support.

The load of each of the groups of four generators may lie-carried in thepower plant installation by means of rods 94 and 88 extending from acentral rigid beam 88 to a mounting bracket liil integral with thereinforced section of the scavenge collector.

By the arrangement shown, longitudinal expansion of the scavengecollector may occur without affecting the mounting of the generator,since the rods 94 and 9B are pivoted on a pin I02 on the support 88, andeach rod is pivoted on a pin I04 in the bracket I80. The weight of eachgroup of four burners is carried through the reinforced section of thescavenge collector so that the remainder of the collector may be made ofa relatively thin material since it carries substantially only thepressure load of the scavenge gas. Furthermore, by reinforcing thescavenge collector so that the generator may be cantilevered directly tothe reinforcing rings, all extraneous supporting structure for thegenerators may be eliminated, thereby materially reducing the weight ofthe supporting structure for the generator.

Since the generators are hung from the rods 04 and 96, and the rods arepivoted on support 98, expansion of the burner structure may occurwithout damage to the supporting structure.- Each group of generatorsmay move toward and away from each other without the necessity forspecial provision for expansion.

It is to be understood that the invention is not limited to the specificembodiment herein illustrated and described, but may be used in otherways without departure from its spirit as defined by the followingclaims. 7

I claim:

1. A power plant including a scavenge collector. an exhaust collectorwithin the scavenge collector, a number of free piston units aroundthescavenge collector, each unit having a scavenge opening, and asurrounding flange adapted to be connected to the scavenge collector,and said unit having an exhaust pipe extending through the scavengeopening and connected to the exhaust collector, said scavenge collectorhaving a reinforcing ring to which the flange is connected.

2. A power plant including a scavenge collector, an exhaust collectorwithin the scavenge collector, a number or free piston units around thescavenge collector, each unit having a scavenge opening, and asurrounding flange adapted to be connected to the scavenge collector,and said unit having an'exhaust pipe extending through the scavengeopening and connected to the exhaustcollector, said scavenge collectorhaving a reinforcing ring "to which the flange is connected, said ringbeing substantially the entire support for the. generators, and means onsaid ring for attaching the ring to a supporting structure.

4. A power plant including a gas collector, a number of free-pistonunits arranged in groups around the collector, said groups being spacedlongitudinally of the collector, a reinforcing ring around the collectorcentrally of each group of free-piston units on which the units of eachgroup are cantilevered, and supporting means movable with respect toeach other, and engaging the longitudinally spaced reinforcing rings forsupporting the groups of generators.

5. A power plant including a gas collector, a number of free-pistonunits arranged in groups around the collector, said groups'being spacedlongitudinally of the collector, each unit having a case within whichthe elements of the unit are mounted, said case having a flangesurrounding a gas discharging opening, a reinforcing ring around thecollector centrally .of each group oi? free-piston units on which theunits of each group are cantilevered, and supporting means movable withrespect to each other and engaging the longitudinally spaced reinforcingrings for supporting the groupsof generators, each of said reinforcingrings having integral flanges to which the flanges on the units aredirectly connected.

.WALTER KENNETH'BODGER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNI' IED STAT ES PATENTS I

